BARACK OBAMA WAS BACK in Chicago and back on the campaign trail, two realms from which he had been absent for a while but which always felt like home. It was April 14, 2011, and Obama had returned to the Windy City to launch his reelection effort with a trio of fund-raisers. Ten days earlier, his people had filed the papers making his candidacy official and opened up the campaign headquarters there. Five hundred and seventy-two days later, the voters would render their judgment. To Obama, Election Day seemed eons away—and just around the corner.

Working his way from two small events for high-dollar donors at fancy restaurants to a crowd of two thousand at Navy Pier, the incumbent served up the old Obama fire. He invoked the memory of the last election night in Grant Park, “the excitement in the streets, the sense of hope, the sense of possibility.” He touted his achievements as “the change we still believe in.” He ended the evening with a “Yes, we can!”

But again and again, Obama cited the burdens of his station. Although he’d always known that as president his plate would be full, the fullness was staggering—from the economic crisis to the swine flu pandemic, the BP oil spill, and the hijacking of an American cargo ship by Somali pirates. (“Who thought we were going to have to deal with pirates?”) He acknowledged the frustrations of many Democrats at the fitfulness of the progress he’d brought about, the compromises with Republicans. He apologized for the fact that his head wasn’t fully in the reelection game. “Over the next three months, six months, nine months, I’m going to be a little preoccupied,” Obama said. “I’ve got this day job that I’ve got to handle.”

The president’s preoccupations at that moment were many and varied, trivial and profound. In public, he was battling with the GOP over the budget and preparing for a face-off over the federal debt ceiling. In secret, he was deliberating over an overseas special-ops raid aimed at a shadowy target who possibly, maybe, hopefully was Osama bin Laden. But the most persistent distraction Obama was facing was personified by Donald Trump, the real estate billionaire and reality show ringmaster who was flirting with making a presidential run under the banner of birtherism—the crackpot conspiracy theory claiming that Obama was born in Kenya and thus was constitutionally ineligible to preside as commander in chief.

Obama had contended with birtherism since the previous campaign, when rumors surfaced that there was no record of his birth in Hawaii. The fringe theorists had grown distractingly shrill and increasingly insistent; after he won the nomination in June 2008, his team deemed it necessary to post his short-form birth certificate on the Web. The charge was lunacy, Obama thought. Simply mental. But it wouldn’t go away. A recent New YorkTimes poll had found that 45 percent of Republicans and 25 percent of voters overall believed he was foreign born. And with Trump serving as a human bullhorn, the faux controversy had escaped the confines of Fox News and conservative talk radio, reverberating in the mainstream media. Just that morning, before Obama departed for Chicago, ABC News’s George Stephanopoulos had asked him about it in an interview, specifically citing Trump—twice.

As Obama made his fund-raising rounds that night, he avoided mentioning Trump, yet the issue remained much on his mind. What confounded him about the problem, beyond its absurdity, was that there was no ready solution. Although Trump was braying for his original long-form birth certificate, officials in Obama’s home state were legally prohibited from releasing it on their own, and the president had no earthly idea where his family’s copy was. All he could do was joke about the topic, as he did at his final event of the night: “I grew up here in Chicago,” Obama told the crowd at Navy Pier, then added awkwardly, “I wasn’t born here—just want to be clear. I was born in Hawaii.”

Obama was looking forward to spending the night at his house in Kenwood, on the city’s South Side—the redbrick Georgian Revival pile that he and Michelle and their daughters left behind when they took up residence in the White House. He arrived fairly late, after 10:00 p.m., but then stayed up even later, intrigued by some old boxes that had belonged to his late mother, Ann Dunham.

Dunham had died seven years earlier, but Obama hadn’t sorted through all her things. Now, alone in his old house for just the third night since he’d become president, he started rummaging through the boxes, digging, digging, until suddenly he found it: a small, four-paneled paper booklet the world had never seen before. On the front was an ink drawing of Kapi‘olani Maternity and Gynecological Hospital, in Honolulu. On the back was a picture of a Hawaiian queen. On one inside page were his name, his mother’s name, and his date of birth; on the other were his infant footprints.

The next morning, Marty Nesbitt came over to have breakfast with Obama. The CEO of an airport parking-lot company, Nesbitt was part of a tiny circle of Chicago friends on whom the president relied to keep him anchored in a reality outside the Washington funhouse. The two men had bonded playing pickup basketball two decades earlier; their relationship was still firmly rooted in sports, talking smack, and all around regular-guyness. After chatting for a while at the kitchen table, Obama went upstairs and came back down, wearing a cat-who-ate-a-whole-flock-of-canaries grin, waving the booklet in the air, and then placing it in front of Nesbitt.

“Now, that’s some funny shit,” Nesbitt said, and burst out laughing.

Clambering into his heavily armored SUV, Obama headed back north to the InterContinental hotel, where he had an interview scheduled with the Associated Press. He pulled aside his senior adviser David Plouffe and press secretary Jay Carney, and eagerly showed them his discovery.

Plouffe studied the thing, befuddled and wary: Is that the birth certificate? he thought.

Carney was bewildered, too, but excited: This is the birth certificate? Awesome.

Obama didn’t know what to think, but he flew back to Washington hoping that maybe, just maybe, he now had a stake to drive through the heart of birtherism, killing it once and for all—and slaying Trump in the bargain. Striding into a meeting with his senior advisers in the Oval Office the next Monday morning, he reached into his suit pocket and whipped out the booklet, infinitely pleased with himself.